PET copolymer composition with enhanced mechanical properties and stretch ratio, articles made therewith, and methods

ABSTRACT

A container is made from a preform comprising a PET Copolymer comprising a diol component having repeat units from ethylene glycol and a non-ethylene glycol diol component and a diacid component having repeat units from terephthalic acid and a non-terephthalic acid diacid component. The total amount of non-ethylene glycol diol component and non-terephthalic acid diacid component is present in the poly(ethylene terephthalate) copolymer in an amount from about 0.2 mole percent to less than 2.2 mole percent. The container is useful in packaging beverages and corresponding methods are disclosed.

CROSS REFERENCE TO RELATED APPLICATION

This application claims priority Under 35 U.S.C. §119 to U.S.provisional patent application Ser. No. 60/423,221 filed on Nov. 1,2002.

FIELD OF THE INVENTION

This invention relates to preforms and their containers made withpoly(ethylene terephthalate)-based resin compositions that possess lowlevels diol and acid modification, such as naphthalenedicarboxylic acidand diethylene glycol. More particularly, this invention relates to lowstretch ratio preforms and their containers, which exhibit enhancedmechanical properties relative to containers made using conventionalpoly(ethylene terephthalate)-based resin compositions.

BACKGROUND OF THE INVENTION

Poly(ethylene terephthalate)-based resins, which are commonly referredto in the industry simply as “PET” even though they may and often docontain minor amounts of additional components, have widely been used tomake containers for carbonated soft drink, juice, water and the like dueto their excellent combination of mechanical and gas barrier properties.As the use of plastics such as PET for packaging increases, concernsregarding the environmental impact of plastic waste are becoming moreand more significant. Source reduction is a preferred strategy forreducing the environmental impact of plastic containers. Sourcereduction saves resources and energy; however, with PET additionalsource reduction is difficult to achieve, because of the physicalperformance requirements necessary for the major applications for thispolymer.

One source reduction opportunity that does exist is related to thedegree of material utilization achieved in blow-molding of PET preformsinto PET containers. The degree of material utilization is defined asthe amount of unoriented polymer present in the sidewall of thecontainer. For large sized containers, the amount of materialutilization is already high, and further increases offer limitedopportunity for source reduction. However, for small sized containers,the amount of material utilization is significantly lower, with degreesof material utilization typically ranging from 80 to 85 percent.Improving material utilization using conventional PET can be achieved byincreasing the stretch ratio of the preform. Increasing the stretchratio of the preform provides an added benefit by increasing themechanical properties of the container, because the stiffness of PET isdirectly affected by the degree of orientation imposed by stretching thepolymer. However, there is a significant cost associated with increasingthe preform stretch ratio. Increasing the preform stretch rationecessarily means increasing the wall thickness of the preform, whichadversely impacts injection molding and blow molding cycle times. Thisconsequently consumes more energy and increases the capital andoperating cost for making PET containers.

Previous methods of source reduction have focused simply on reducing theweight of the container, with a concomitant reduction in the sidewallthickness of the resulting container. This approach inherentlysacrifices the mechanical integrity of the container, since sidewallrigidity relates to the second power of the thickness. Although inprinciple the sidewall rigidity of a container could be maintained byincreasing the modulus of the polymer, in practice this is difficult toachieve. In addition, sidewall rigidity varies only to the first powerof modulus; therefore, a much higher increase in the modulus would berequired to counter-balance any thickness reduction. While an increasein the molecular weight of the PET or crystallinity level of thecontainers can increase the modulus of PET, these approaches haveinherent limits. An even minor increase in molecular weight alsoincreases the melt viscosity of the PET, which can lead to significantlygreater polymer degradation during the melt processing that produces thepreforms. To increase the crystallinity level of the containersubstantially, additional steps in the container manufacturing process,such as heat-setting at high temperature, are required. Other means toachieve much higher crystallinity of containers, such as throughnucleation agents or hyper-stretching, have not been successful.

U.S. Pat. Nos. 5,631,054 and 5,162,091 described methods to increase themechanical properties of PET through use of specific low molecularweight additives. Those additives provided modest improvements to thetensile modulus of PET. However, the amount of additives required ishigh (1-5% by weight), and the additives claimed are relativelyexpensive compared to the cost of PET. In addition, because theseadditives were not part of the polymer chains, they are potentiallyextractable, which is detrimental to their use in food contactapplications.

Thus, there exists a need in the art for a container that has a highdegree of material utilization, is lighter weight, has sufficientmechanical properties, and consumes less energy in its production.Accordingly, it is to the provision of such that the present inventionis directed.

SUMMARY OF THE INVENTION

This invention addresses the above-described need for lighter weightcontainers by providing an injection molded preform having an open endedmouth forming portion, an intermediate body forming portion, and aclosed base-forming portion. In one embodiment, the preform comprises apoly(ethylene terephthalate) copolymer (hereinafter “PET Copolymer”)comprising a diol component having repeat units from ethylene glycol anda non-ethylene glycol diol component and a diacid component havingrepeat units from terephthalic acid and a non-terephthalic acid diacidcomponent. The total amount of non-ethylene glycol diol component andnon-terephthalic acid diacid component is present in the PET Copolymerin an amount from about 0.2 mole percent to less than about 2.2 molepercent. The mole percentages are based on 100 mole percent diacidcomponent and 100 mole percent diol component. This definition isapplicable to mole percentages throughout this specification. Thepreform, the container and corresponding methods of making each areadditional embodiments of this invention.

In another embodiment, a preform for use in making a container comprisesa PET Copolymer comprising a diol component having repeat units fromethylene glycol and a non-ethylene glycol diol component and a diacidcomponent having repeat units from terephthalic acid and anon-terephthalic acid diacid component. The total amount of non-ethyleneglycol diol component and non-terephthalic acid diacid component ispresent in the PET Copolymer in an amount from about 0.2 mole percent toless than about 3.0 mole percent based on 100 mole percent of the diolcomponent and 100 mole percent of the diacid component. Furthermore, thenon-ethylene glycol diol component is present in an amount of from about0.1 to about 2.0 and the non-terephthalic acid diacid component ispresent in an about of about 0.1 to about 1.0.

In preferred embodiments, the preforms are designed to have a stretchratio in the range from about 8 to about 12, enabling the preforms tohave a reduced wall thickness. Thus the cycle time for manufacture ofthe preforms is reduced. Because the material utilization is higher,less material needs to be used and the cost of goods is lowered, whilethe containers produced exhibit improved thermal stability and sidewallrigidity characteristics.

In still another embodiment of the present invention, a method forreducing the cycle time for making a container comprises the steps of:

-   -   (1) providing a PET Copolymer melt comprising a diol component        having repeat units from ethylene glycol and a non-ethylene        glycol diol component and a diacid component having repeat units        from terephthalic acid and a non-terephthalic acid diacid        component, wherein the total amount of non-ethylene glycol diol        component and non-terephthalic acid diacid component is present        in the PET Copolymer in an amount from about 0.2 mole percent to        less than about 2.2 mole percent,    -   (2) then injecting the PET Copolymer into a mold,    -   (3) then cooling the mold and the contained polymer,    -   (4) then releasing from the mold a preform,    -   (5) then reheating the preform, and    -   (6) then blow molding the preform into a container.

The cycle time for making the container is reduced as compared to asecond cycle time for making a second container comprising apoly(ethylene terephthalate) resin having comonomer modification greaterthan about 2.2 mole percent of a combination of a non-ethylene glycoldiol component and a non-terephthalic acid diacid component.

Thus, embodiments of this invention provide two sets of improvements. Inone set, the PET Copolymer is used with a conventional preform design toproduce a container with enhanced mechanical properties, highercrystallinity and improved shelf life. In the other set, the PETCopolymer is used with a redesigned preform that has a stretch ratio offrom about 8 to about 12, a reduced preform wall thickness, and reducedcycle time to produce a container of similar or improved qualitycompared to a container produced using conventional PET resin and aconventional preform design.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a sectional elevation view of an injection molded preformhaving a conventional configuration, made with the PET Copolymer inaccordance with a preferred embodiment of this invention.

FIG. 2 is a sectional elevation view of an injection molded preformhaving an unconventional configuration in accordance with a preferredembodiment of this invention.

FIG. 3 is a sectional elevation view of a blow molded container madefrom the preform of FIG. 1 in accordance with a preferred embodiment ofthis invention.

DETAILED DESCRIPTION OF THE INVENTION

In the present invention, a PET Copolymer is made into an injectionmolded preform which is then blow molded into a container. The preformcomprises an open ended mouth forming portion, an intermediate bodyforming portion, and a closed base forming portion. The preformcomprises a PET Copolymer comprising a diol component having repeatunits from ethylene glycol and a non-ethylene glycol diol component anda diacid component having repeat units from terephthalic acid and anon-terephthalic acid diacid component, wherein the total amount ofnon-ethylene glycol diol component and non-terephthalic acid diacidcomponent is present in the PET Copolymer in an amount from about 0.2mole percent to less than about 2.2 mole percent. The mole percentagesof diol components and diacid components include all residual comonomersin the PET Copolymer composition such as those formed during or passingthrough the manufacturing process of the PET Copolymer. In all instancesthroughout the specification, the PET Copolymer is based on a total of200 mole percent including 100 mole percent of the diol component and100 mole percent of the diacid component.

The amount of each of the non-ethylene glycol diol component andnon-terephthalic acid diacid component in the PET Copolymer can vary tosome extent within the total amount of both, which is from about 0.2mole percent to less than about 2.2 mole percent. Preferably, the totalamount of non-ethylene glycol diol component and non-terephthalic aciddiacid component is present in the PET Copolymer in an amount from about1.1 mole percent to about 2.1 mole percent, and even more preferably inan amount from about 1.2 mole percent to about 1.6 mole percent. Repeatunits from the non-terephthalic acid diacid component are preferablypresent in the PET Copolymer in an amount from about 0.1 to about 1.0mole percent, more preferably in an amount from about 0.2 to about 0.75mole percent, still more preferably in an amount from about 0.25 toabout 0.6 mole percent, and yet more preferably in an amount from about0.25 to less than about 0.5 mole percent. The repeat units from thenon-ethylene glycol diol component are preferably present in the PETCopolymer in an amount from about 0.1 to about 2.0 mole percent, morepreferably in an amount from about 0.5 to about 1.6 mole percent, andeven more preferably in an amount from about 0.8 to about 1.3 molepercent. The PET Copolymer preferably has an intrinsic viscosity (IV),measured according to ASTM D4603-96, from about 0.6 to about 1.1 dL/g,more preferably from about 0.7 to about 0.9, and even more preferablyfrom about 0.8 to about 0.84. Desirably, the PET resin of this inventionis a reaction grade resin, meaning that the PET resin is a directproduct of a chemical reaction between comonomers and not a polymerblend.

In another embodiment of the invention, a preform for use in making acontainer comprises a PET Copolymer comprising a diol component havingrepeat units from ethylene glycol and a non-ethylene glycol diolcomponent and a diacid component having repeat units from terephthalicacid and a non-terephthalic acid diacid component. The total amount ofnon-ethylene glycol diol component and non-terephthalic acid diacidcomponent present in the PET Copolymer is in an amount from about 0.2mole percent to less than about 3.0 mole percent based on 100 molepercent of the diol component and 100 mole percent of the diacidcomponent. The non-ethylene glycol diol component is present in anamount of from about 0.1 to about 2.0 and the non-terephthalic aciddiacid component is present in an about of about 0.1 to about 1.0.Preferably, the total amount of non-ethylene glycol diol component andnon-terephthalic acid diacid component is present in an amount fromabout 0.2 mole percent to less than about 2.6 mole percent.

The non-terephthalic acid diacid component can be any of a number ofdiacids, including adipic acid, succinic acid, isophthalic acid (IPA),phthalic acid, 4,4′-biphenyl dicarboxylic acid, naphthalenedicarboxylicacid, and the like. The preferred non-terephthalate acid diacidcomponent is 2,6-naphthalenedicarboxylic acid (NDC). The non-ethyleneglycol diols contemplated in this invention includecyclohexanedimethanol, propanediol, butanediol, and diethylene glycol.Of these, diethylene glycol (DEG) is preferred since it is alreadynaturally present in the PET Copolymer. The non-terephthalic acid diacidcomponent and the non-ethylene glycol diol component may also bemixtures of diacids and diols, respectively.

The levels of DEG in PET Copolymers of the present invention range fromabout 0.1 to about 2.0 mole percent, which is below the typical residuallevels of DEG present in the manufacture of conventional PET(hereinafter “Conventional PET”). Conventional PET typically containsfrom about 2.4 to about 2.9 mole percent DEG, which is equivalent tomore commonly referenced weight percent values of about 1.3 to about1.6. Those skilled in the art of PET manufacture generally regard DEG asa harmless by-product of the polymer manufacture; consequently, littleeffort has been directed toward reduction of DEG levels in PET intendedfor use in containers. Thus, modifications to the PET production processfor containers must occur to achieve the lower DEG levels in the PETCopolymer of the present invention. Any method suitable for reducing DEGcontent of polyester can be employed. Suitable methods include reducingthe mole ratio of diacid or diester relative to ethylene glycol in theesterification or transesterification reaction; reducing the temperatureof the esterification or transesterification reaction, addition ofDEG-suppressing additives, including tetra-alkyl ammonium salts and thelike; and reduction of the DEG content of the ethylene glycol that isrecycled back to the esterification or transesterification reaction.

In desirable embodiments, the preforms have a stretch ratio in the rangefrom about 8 to about 12 when used to make containers, and moredesirably from about 8 to about 10. The stretch ratio as used hereinrefers to the nomenclature that is well known in the art and is definedas following:Stretch ratio=(maximum container diameter/internal preformdiameter)×[(height of container below finish)/(height of preform belowfinish)]

The natural stretch ratio is an inherent property of a polymer. Themeasurement of the free blow volume of a polymer relative to a preform,which is used in the Examples herein, provides a method to measure thenatural stretch ratio of a polymer. The natural stretch ratio of apolymer influences the preform design by determining the stretch ratiolimitations of a preform used in the blow molding process for making acontainer. A polymer with a lower natural stretch ratio allows a preformto be designed with a lower stretch ratio. Whenever the stretch ratio ofa preform is lower, the sidewall thickness of the preform required tomake a bottle of a target sidewall thickness can be reduced. Animportant factor in blow molding lightweight containers is also uniformwall thickness distribution, especially in the label panel area. Usingpolymers with lower natural stretch ratios inherently causes morematerial to be uniformly oriented and distributed during the blowmolding process. With an understanding of the natural stretch ratio of apolymer, preform dimensions such as height, inside diameter, and wallthickness can be selected so that the preform can be blow molded into acontainer having certain selected physical properties such as weight,height, maximum diameter, thermal stability, and sidewall rigidity.

In another embodiment of the present invention, a method for reducingthe cycle time for making a container comprises the steps of:

-   -   (1) providing a PET Copolymer melt comprising a diol component        having repeat units from ethylene glycol and a non-ethylene        glycol diol component and a diacid component having repeat units        from terephthalic acid and a non-terephthalic acid diacid        component, wherein the total amount of non-ethylene glycol diol        component and non-terephthalic acid diacid component is present        in the PET Copolymer in an amount from about 0.2 mole percent to        less than about 2.2 mole percent,    -   (2) then injecting the PET Copolymer into a mold,    -   (3) then cooling the mold and the contained polymer,    -   (4) then releasing from the mold a preform,    -   (5) then reheating the preform, and    -   (6) then blow molding the preform into a container.

The cycle time for making the container according to the steps above isreduced as compared to a second cycle time for making a second containercomprising a poly(ethylene terephthalate) resin having comonomermodification greater than about 2.2 mole percent of a combination of anon-ethylene glycol diol component and a non-terephthalic acid diacidcomponent.

In another method embodiment, a method for making a container comprisesblow molding an injection molded preform that has an open ended mouthforming portion, an intermediate body forming portion, and a closed baseforming portion, The preform comprises a PET Copolymer comprising a diolcomponent having repeat units from ethylene glycol and a non-ethyleneglycol diol component and a diacid component having repeat units fromterephthalic acid and a non-terephthalic acid diacid component. Thetotal amount of non-ethylene glycol diol component and non-terephthalicacid diacid component present in the PET Copolymer is in an amount fromabout 0.2 mole percent to less than about 2.2 mole percent.

In still another method embodiment, a method for making a preform foruse in making containers comprises injection molding a PET Copolymer,which comprises a diol component having repeat units from ethyleneglycol and a non-ethylene glycol diol component and a diacid componenthaving repeat units from terephthalic acid and a non-terephthalic aciddiacid component. The total amount of non-ethylene glycol diol componentand non-terephthalic acid diacid component present in the PET Copolymer:is in an amount from about 0.2 mole percent to less than about 2.2 molepercent.

In the method embodiments, the PET Copolymer preferably comprises2,6-naphthalenedicarboxylic acid as the non-terephthalic acid diacidcomponent present in an amount from about 0.1 to about 1.0 mole percentand diethylene glycol as the non-ethylene glycol diol component presentin the PET Copolymer in an amount from about 0.1 to about 2.0 molepercent. Preferably, the preform has a stretch ratio in the range fromabout 8 to about 12 and more preferably in the range from about 8 toabout 10.

To understand the significance of the present invention, anunderstanding of the conventional process of making containers isneeded. Firstly, PET pellets that are obtained from a conventionalpolyester esterification/polycondensation process are melted andsubsequently formed into preforms through an injection molding process.Secondly, the preforms are heated in an oven to a temperature above thepolymer's glass transition temperature, and then formed into containersvia a blow molding process. The desired end result is clear containerswith sufficient mechanical and barrier properties to provide appropriateprotection for the contained beverage or food product.

An important consideration in producing clear or transparent containersis to first produce clear or transparent preforms. During the injectionmolding step thermally induced crystallization can occur in theconversion of the polymer to a preform. Thermally inducedcrystallization tends to form large crystallites in the polymer, with aconcomitant formation of haze. In order to minimize the formation ofcrystallites and thus have clear preforms, the rate of thermalcrystallization needs to be slow enough so that preforms with little orno crystallinity can be produced. However, if the rate of thermalcrystallization is too low, the production rates of PET resin can beadversely affected, since PET must be thermally crystallized prior tosolid-state polymerization, a process used to increase the molecularweight of PET and simultaneously remove unwanted acetaldehyde. Solidstate polymerization increases the molecular weight of the polymer sothat a container made from the polymer will have the requisite strength.Prior art techniques for reducing thermal crystallization rate includethe use of PET containing a certain amount of co-monomers. The mostcommonly used comonomer modifiers are isophthalic acid or.1,4-cyclohexanedimethanol, which are added at levels ranging from 1.5 to3.0 mole %.

Counterbalancing the need to reduce the rate of thermal crystallizationduring injection molding is the need to increase the rate ofstrain-induced crystallinity that occurs during blow molding.Strain-induced crystallinity results from the rapid mechanicaldeformation of PET, and generates extremely small, transparentcrystallites. The amount of crystallinity present in the containersidewall correlates with the strength and barrier performance of thecontainer. Previously, it has been demonstrated that increasing the DEGcontent of PET from 2.9 to 4.0 mole percent causes an increase incrystallization rates of PET compared to Conventional PET containingbetween 2.4 to 2.9 mole percent DEG. The rationale for this phenomenonis that the increased polymer chain flexibility resulting from thehigher DEG content allows for more rapid ordering and packing of thepolymer chains into polymer crystals.

In the PET Copolymer of the present invention both a reduced rate ofthermal crystallization and an increased rate of strain-inducedcrystallization is unexpectedly found to occur by the comonomermodification of non-terephthalic acid diacid component at about 0.1 toabout 1.0 mole percent and of non-ethylene glycol diol component atabout 0.1 to about 2.0 mole percent, respectively. The non-terephthalicacid diacid such as NDC is believed to reduce the thermalcrystallization rate due to the rigidity of the NDC moiety hinderingpolymer chain flexibility, and thus makes formation of crystallites moredifficult. The addition of NDC has also been discovered to enhance thestiffness of the PET chains and results in an unexpected increase in thesidewall rigidity of the containers made from PET Copolymer. Furthermoreand contrary to expectations, reducing the DEG content to less thanabout 2.0 mole percent in the PET Copolymer results in an increase inthe rate of strain-induced crystallization relative to Conventional PETcontaining between 2.4 and 2.9 mole percent DEG.

A consequence of this unique combination of low amounts of DEG and NDC,at least in preferred embodiments, is a reduction in the natural stretchratio of PET Copolymer as compared to that of Conventional PET. Thephysical dimensions of the preform can therefore be altered so as tomake a thinner walled preform that produces a lighter weight containerthat has an acceptable level of strength and similar container sidewallthickness compared to containers made from Conventional PET usingconventional preform designs, or to make similar weight containershaving a higher level of strength and greater container sidewallthickness. The physical properties of the preform can also be selectedto reduce the preform injection molding cycle time and the containerblow molding cycle time without compromising the container strength orshelf life of the container contents.

By using the PET Copolymer of the present invention, containers thathave enhanced mechanical properties, higher crystallinity, thickersidewalls, and improved shelf-life can be made utilizing preforms thathave conventional stretch ratios of about 14. Alternatively and inpreferred embodiments, unconventional preforms; can be designed to havea longer length and thinner walls and that have a stretch ratio of fromabout 8 to about 12. Containers made using the PET Copolymer of thepresent invention and such unconventional preforms exhibit improvedmaterial utilization, stiffness, and higher levels of strain inducedcrystallinity during the blow molding process as compared toconventional preforms made from Conventional PET even when the preformshave reduced sidewall thickness and lower stretch ratios than that ofconventional preforms made with Conventional PET.

The present invention can be more fully appreciated when comparingcontainer properties relative to the preform stretch ratio. A preformdesigned to have a stretch ratio of about 14 and a sidewall thickness ofabout 3.2 mm using Conventional PET having DEG content above 2.0 molepercent will result in a blow molded container having a sidewallthickness of about 0.23 mm. When using the same preform design with thePET Copolymer of the present invention, the blow molded container willhave a sidewall thickness of about 0.35 mm. To obtain the same resultingcontainer sidewall thickness using the PET Copolymer, the preform needsto be redesigned to be longer and have a sidewall thickness of 2.3 mm.This thinner sidewall preform exhibits improved cycle times and reducedenergy usage as well as a reduced total weight as compared with preformsmade of Conventional PET resins, while at the same time producing anequivalent or improved container. To further illustrate, a preform madewith Conventional PET using the redesigned preform having a sidewallthickness of 2.28 mm would result in a useless container because thesidewall thickness of the container would be only 0.16 mm, which wouldnot provide enough structural integrity to the container, and would alsoexhibit reduced shelf-life for carbonated beverages.

Thus, an important benefit of the reduced natural stretch ratio of thePET Copolymer of the present invention is the redesign of preforms sothat a longer-length, thinner-walled preform can be designed to achievethe same or better final PET container properties as obtained fromConventional PET and conventional preform designs. As well known tothose skilled in the art, the sidewall thickness of the preformcorrelates with the injection molding cooling time. The cooling time isproportional to the square of the wall thickness. Since injectionmolding cycle time is to a large degree determined by cooling time, thepreform design of the present invention will substantially reduce theinjection molding cycle time. A thinner-walled preform is also easier toreheat since it will take less time for heat to transfer throughout thepreform sidewall. This potentially can reduce the blow molding reheatand beat saturation time, resulting in an improvement in productivityand a reduction in energy usage in the blow molding process.

The light weighting potential for a container can be illustrated withtwo tests: thermal expansion and sidewall deflection as described in thefollowing sections. Both tests demonstrate the mechanical properties ofthe bottles of thermal stability and sidewall rigidity, respectively.For the same resin composition, a lighter weight bottle has lowermechanical strength, poorer thermal stability (and concomitantly greaterthermal expansion), and less sidewall rigidity (or greater sidewalldeflection). The low DEG, low NDC PET Copolymer of the present inventiondisplays enhanced performance in both thermal stability and sidewallrigidity tests. Such performance is possibly caused by the increasedcrystallinity of the PET Copolymer and the decreased moisture sorptiontherein. Both of these factors can substantially decrease creep, whichis the dimensional change under stress of a container measured by thechange in diameter and height. This is an important factor, because mostcontainers undergo some stress during and after the filling process.Therefore, thermal expansion and sidewall deflection tests are usedherein to compare the performance of containers, and especially theperformance of pressurized containers.

In preferred embodiments, containers of this invention include bottles,drums, carafes, and coolers, and the like. As is well known to thoseskilled in the art, such containers can be made by blow molding aninjection molded preform. Examples of suitable preform and containerstructures and methods for making the same are disclosed in U.S. Pat.No. 5,888,598, the disclosure of which is expressly incorporated hereinby reference in its entirety. Other preform and container structures,not disclosed in U.S. Pat. No. 5,888,598, are described herein as well.

Turning to the FIGS. 1-3, a polyester preform 10 having a conventionalconfiguration is illustrated in FIG. 1 and a polyester preform 11 havinga configuration in accordance with an embodiment of this invention isillustrated in FIG. 2. These preforms 10 and 11 in FIGS. 1 and 2 eachhave the same components, and therefore, like reference numeralsindicate like components throughout the Figs., but the dimensions of thepreforms are different. The dimensions in FIGS. 1 and 2 are not drawn toscale.

The preforms 10 and 11 are made by injection molding the PET Copolymerof this invention and comprise a threaded neck finish 12 whichterminates at its lower end in a capping flange 14. Below the cappingflange 14, there is a generally cylindrical section 16 which terminatesin a section 18 of gradually decreasing external diameter so as toprovide for an increasing wall thickness. Below the section 18 there isan elongated body section 20. The height of the preform is measured fromthe capping flange 14 to a closed end 21 of the elongated body section20.

The preforms 10 and 11 illustrated in FIGS. 1 and 2 can each be blowmolded to form a container 22 illustrated in FIG. 3. The container 22comprises a shell 24 comprising a threaded neck finish 26 defining amouth 28, a capping flange 30 below the threaded neck finish, a taperedsection 32 extending from the capping flange, a body section 34extending below the tapered section, and a base 36 at the bottom of thecontainer. The height of the container is measured from the cappingflange 30 to a closed end at the base 36. The container 22 is suitablyused to make a packaged beverage 38, as illustrated in FIG. 3. Thepackaged beverage 38 includes a beverage such as a carbonated sodabeverage disposed in the container 22 and a closure 40 sealing the mouth28 of the container.

According to preferred embodiments of this invention, the intermediatebody forming portion of the preform has a wall thickness from 1.5 to 8mm. Furthermore, according to preferred embodiments, the intermediatebody forming portion of the preform has an inside diameter from 10 to 30mm, and the height of the preform, which extends from the closed end ofthe preform opposite the finish to the finish, is from 50 to 150 mm.Preferably, containers made in accordance with preferred embodiments ofthis invention have a volume within the range from 0.25 to 3 liters anda wall thickness of 0.25 to 0.65 mm.

In this specification, reference is made to dimensions of the preforms10 and 11 and the resulting containers 22. The height H of the preformsis the distance from the closed end 21 of the preform opposite thefinish 12 to the capping flange 14 of the finish. The inside diameter IDof the preforms 10 and 11 is the distance between the interior walls ofthe elongated body section 20 of the preforms. The wall thickness T ofthe preforms 10 and 11 is measured at the elongated body section 20 ofthe preforms also. The height H′ of the containers 22 is the distancefrom the closed end of the base 36 of the container opposite the finish26 to the capping flange 30 of the finish. The maximum containerdiameter MD is the diameter of the container at its widest point alongthe height of the container 22. The hoop stretch ratio of the preformsequals the maximum container diameter divided by the internal preformdiameter and the axial stretch ratio equals the height of containerbelow the finish divided by the height of preform below the finish. Thestretch ratio of the preforms equals the product of the hoop stretchration and the axial stretch ratio.

The preforms 10 and 11, container 22, and packaged beverage 38 are butexemplary embodiments of the present invention. It should be understoodthat the PET Copolymers of the present invention can be used to make avariety of preforms and containers having a variety of configurations.

The present invention is described above and further illustrated belowby way of examples, which are not to be construed in any way as imposinglimitations upon the scope of the invention. On the contrary, it is tobe clearly understood that resort may be had to various otherembodiments, modifications, and equivalents thereof which, after readingthe description herein, may suggest themselves to those skilled in theart without departing from the spirit of the present invention and/orscope of the appended claims.

EXAMPLE 1

Different PET resins were injection molded with a lab-scale Arburg 75unit cavity injection machine into conventional preform molds with astretch ratio about 12.3 but with different gram weights. Resins werepre-dried to moisture levels below 30 parts per million (ppm). Thepreforms were then stretch blow molded with a SBO-1 stretch blow-moldingmachine into 500 ml Coca-Cola Contour bottles. A description of theweights and compositions of the samples is listed in Table 1. The #3Samples are representative of embodiments of the present invention andthe #1 and #2 Samples are comparative. TABLE 1 Gram DEG NDC IPA Sampleweight mole % mole % mole % #1-27 27 2.89 0 3 #2-27 27 1.45 0 2.5 #3-2727 1.45 0.5 0 #1-26 26 2.89 0 3 #2-26 26 1.45 0 2.5 #3-26 26 1.45 0.5 0#1-24 24 2.89 0 3 #2-24 24 1.45 0 2.5 #3-24 24 1.45 0.5 0

EXAMPLE 2

The containers produced in Example 1 were subjected to a standardthermal stability test, which involves filling the containers withcarbonated water, holding them at 22 deg C. for 24 hours, subjectingthem to a temperature of 38 deg C. for an additional 24 hours, and thenmeasuring the dimensional changes that occurred relative to the unfilledcontainers. The data in Table 2 shows that low DEG, low NDC PETCopolymers of the #3 Samples from Example 1 have increased thermalstability property for pressurized containers over that of thecomparable Samples #1 and #2, as evidenced by lower thermal expansionresults. The 24 gram Sample #3 exhibits enhanced thermal stabilitycompared to the 27 gram Sample #1 control. TABLE 2 Label Diameter PinchDiameter Sample Expansion (%) Expansion (%) #1-27 3.1 5.4 #2-27 2.6 5.6#3-27 2.3 4.8 #1-26 3.2 5.4 #2-26 3.9 7.5 #3-26 2.7 5.4 #1-24 3.6 5.8#2-24 2.4 4.9 #3-24 2.6 4.7

EXAMPLE 3

In Example 3, containers made in Example 1 were tested for sidewallrigidity using a sidewall deflection test. The sidewall deflection testis designed to measure the amount of force required to deflect the labelpanel of PET bottles 12 mm (0.47″) with an 8 mm (0.32″) round tip probeat a cross-head speed of 508 mm/min. This measurement gives informationabout the rigidity of the container. The greater the force required toachieve a specific sidewall deflection, the greater the rigidity of thebottle sidewall.

The data in Table 3 shows that the low DEG, low NDC PET Copolymers ofthe #3 Samples from Example 1 have increased sidewall rigidity over thatof the comparable Samples #1 and #2. The sidewall rigidity of the 24gram sample #3 is equivalent to 27 gram sample #1 control. TABLE 3Sidewall Deflection Sample (Kgf.) #1-27 4.87 #3-27 5.36 #2-27 5.35 #1-264.25 #3-26 4.67 #2-26 4.53 #1-24 4.14 #3-24 4.80 #2-24 4.50

EXAMPLE 4

The data in Table 4 shows that the crystallinity of containers preparedfrom low DEG, low NDC PET Copolymer samples using a conventional preformdesign are higher than that of containers prepared from Conventional PETusing the same preform design. The PET containers having thecompositions shown in Table 4 above were made in the same manner as thecontainers in Example 1.

The PET Copolymer made from 1.09 mole percent DEG and 0.5 mole percentof NDC has a significantly higher crystallinity than that of the otherformulas. The containers made from the PET Copolymers, however, areclear and haze-free, which indicates that in spite of the increasedcrystallinity of these resins, the rate of thermal crystallization isstill sufficiently slow that minimal crystallization occurs under theinjection molding conditions employed. The higher container sidewallcrystallinity is believed to contribute to the improved thermalstability and the improved sidewall rigidity. TABLE 4 Strain CompositionInduced mole % mole % mole % Crystallinity IPA DEG NDC (%) 3.0 2.72 025.8 3.0 1.09 0 22.4 3.0 2.00 0 22.3 0 1.09 0.5 28.8 0 1.09 0.5 29.9 01.09 1 26.4

EXAMPLE 5

The free blow volumes of PET preforms from Example 1 and PET preformsmade in accordance with the procedure in Example 1 were determined byheating the preforms to 105 deg C., and then blowing balloons from theheated preforms with 125 psig air pressure. The volume of the resultingballoons was measured by filling the balloons with water, anddetermining the volume of water contained in the balloons by weighing.The results of these measurements are shown in Tables 5 and 6. The freeblow volume is directly correlates to the natural stretch ratio of thepolymers. Under the same free blow conditions, the higher the free blowvolume, the higher the natural stretch ratio of the polymer. Theseresults show that the 1.45 mole percent DEG and the 0.5 mole percent NDCcontaining PET Copolymer exhibits a 25 to 47 percent reduction in thefree blow volume relative to the control. This is equivalent to an 18 to30 percent reduction in the natural stretch ratio of the resin. TABLE 5Example 1 Free Blow Samples Volume(ml) #1-27 2099.76 #2-27 1756.88 #1-241480.18 #2-24 1480.52 #3-24 1114.49

TABLE 6 Additional PET Copolymer Samples for 23 g preform IPA DEG NDCFree Blow (mole %) (mole %) (mole %) Volume (ml) 3.0 2.72 0 2079 3.01.09 0 2092 3.0 2.00 0 2205 0 1.09 0.5 1523

EXAMPLE 6

In order to further demonstrate the benefit of the PET Copolymer of thepresent invention, light-weighted preforms and bottles were produced.Instead of the normal 27 g preform for 500 ml bottles, 23 g preformswere produced and were blown into the same 500 ml bottle mold used inExample 1. The injection molding was performed with a lab-scale Arburg75 unit cavity injection machine into a conventional preform mold asillustrated in FIG. 1. The preforms were then stretch blow molded with aSBO-1 stretch blow molding machine into 500 ml Coca-Cola Contour bottleas in FIG. 3. The preform IV was measured according to ASTM D 4603-96and the sidewall deflection and thermal expansion were measured asdescribed above.

The data in Table 7 shows that the combination of low DEG, low NDC PETCopolymer has higher crystallinity, higher sidewall rigidity andincreased thermal stability as compared to conventional resincompositions. TABLE 7 Bottle Resin Composition Sidewall Sidewall Thermalmole % mole % mole % IV Thickness Deflection Expansion IPA DEG NDC(dL/g) (mm) (Kgf) (%) 3.00 2.72 0 0.794 0.23 6.49 3.60 3.00 1.09 0 0.7820.25 7.25 2.80 3.00 2.00 0 0.773 0.25 6.69 2.50 0 1.09 0.5 0.779 0.257.30 2.20 0 1.09 1 0.788 0.24 6.86 3.00

EXAMPLE 7

In order to demonstrate the effect of reduced natural stretch ratio oninjection molding cycle time, two PET resins were made, a ConventionalPET resin having a conventional formula and a PET Copolymer made inaccordance with an embodiment of this invention. The compositions areshown in Table 8. The free blow volumes of the Conventional PET resinand the PET Copolymer were determined in accordance with the proceduredescribed above and four sets of preforms, 7A, 7B, 7C, and 7D, weremade. Preforms 7A and 7C were both made with the Conventional PET resinusing with a conventional preform design (Conv) as illustrated inFIG. 1. Preforms 7B and 7D were both made with the PET Copolymer usingan unconventional preform design (Uncon) as illustrated in FIG. 2. Thephysical dimensions and molding cycle times of the preforms are setforth in Table 9. TABLE 8 IPA (mole %) DEG (mole %) NDC (mole %)Conventional 3 2.72 0 PET PET Copolymer 0 1.09 0.5

TABLE 9 Preform 7A 7B 7C 7D Resin Conventional PET Conventional PET PETCopolymer PET Copolymer Design Conv Uncon Conv Uncon Preform weight 2424 27 27 (grams) Hoop stretch 4.86 4.93 5.24 4.35 ratio Axial stretch2.52 1.95 2.34 1.95 ratio Preform stretch 12.25 9.61 12.26 8.48 ratioHeight (mm) 80.74 103.99 86.95 103.99 Inside diameter 13.69 13.50 12.6915.30 (mm) Wall 3.43 2.65 3.86 2.80 thickness (mm) Cycle Time 23.6 17.928.5 21.0 (sec)

The data in Table 9 demonstrates that the injection molding cycle timecan be reduced and the injection molding productivity can be increasedby 24 to 26% at the same preform weight by using the PET Copolymer madein accordance with an embodiment of this invention when used inconjunction with a preform designed to take advantage of the lowernatural stretch ratio of the PET Copolymer resin.

EXAMPLES 8-15

The following preforms whose physical properties are set forth in Table10 illustrate additional embodiments of this invention. Each of Examples8-15 are made with the PET Copolymer Resin identified in Table 8 andhave configurations generally like that of preform 11 illustrated inFIG. 2. TABLE 10 Example 8 9 10 11 12 13 14 15 Preform 24 24 24 27 27 2727 23 weight (grams) Hoop stretch 4.86 5.0 4.35 4.93 4.35 4.86 5.0 4.67ratio Axial stretch 2.2 2.06 2.2 1.95 2.2 2.2 2.06 2.52 ratio Preform10.69 10.3 9.57 9.61 9.57 10.69 10.3 11.76 stretch ratio Height 92.4898.49 92.48 103.99 92.48 92.48 98.49 80.73 (mm) Inside 13.68 13.3 15.2913.5 15.29 13.68 13.30 14.24 diameter (mm) Wall 2.95 2.8 2.64 3.06 3.153.4 3.33 3.15 thickness (mm)

EXAMPLE 16

The data in Table 11 below shows the comparison of the free blow volumeand crystallinity of various PET resins. In this Example, the free-blowpressure used was 95 psig. In this Example, the PET Copolymers of thepresent invention having low DEG and low NDC content exhibit a reductionin free blow volume of 21 to 27 percent relative to Conventional PETresin. TABLE 11 Resin Composition mole % mole % mole % Free blow StrainInduced IPA DEG NDC volume (ml) Crystallinity (%) 3 2.80 0 713 27.1 01.60 0 532 28.1 0 1.60 0.25 542 27.8 0 1.60 0.50 520 27.0 0 1.60 1.00560 28.1 0.50 1.60 0 529 27.2

EXAMPLE 17

In this Example, the sidewall deflection test was performed on the freeblow bubbles of Example 16 according to the method described above.Because the bubble volumes were different for each resin due to theirdifferent inherent natural stretch ratio, the rigidity values werenormalized by the bubble diameter and bubble thickness. The normalizedvalues are shown in Table 12. TABLE 12 Resin Composition mole % IPA mole% DEG mole % NDC Rigidity (Kgf/cm) 3 2.80 0 16.6 0 1.60 0 25.0 0 1.600.25 27.9 0 1.60 0.50 29.3 0 1.60 1.00 25.2These results show that a maximum sidewall rigidity is obtained whenabout 0.5 mole % NDC is present as a comonomer.

EXAMPLE 18

Two resins, a PET Copolymer made in accordance with an embodiment ofthis invention and a Conventional PET resin were injection molded intopreforms on a 48 cavity Husky XL 300 machine. The control was moldedinto a 52-gram 2-L preform with sidewall thickness of 3.93 mm, while thePET Copolymer was molded into a 50-gram 2-L preform with a sidewallthickness of 3.71 mm. Both preforms were of conventional design. Thepreforms were then blown into bottles using a Sidel SBO 16 machine. Thebottles were tested for thermal stability, sidewall deflection, andshelf life.

The thermal stability of the bottles made from the two resins weretested as in the previous Examples. The results set forth in Table 13show that with the PET Copolymer, a 50-gram bottle performed similarlyor better than the 52-gram control, in spite of the 2-g light weightingin the bottles. TABLE 13 % Height % Diameter Max. Fill Point ResinChange Increase Drop (in) PET Copolymer 2.0 1.72 1.541 50 gram preformConventional PET 1.9 2.30 1.562 52 gram preform

The sidewall deflection tests were performed on the above describedbottles as per the test method described hereinbefore. The results setforth in Table 14 show that the bottles made from the PET Copolymerperformed better than bottles made from the control, even though thebottles made from the PET Copolymer weigh 2 grams less than the bottlesmade from the Conventional PET.

The bottles from both the PET Copolymer and Conventional PET resins werefilled with 385.84 Kpa of carbon dioxide and tested for shelf life. Theshelf life of the bottles were defined as the time for the bottle tolose 17.5% of the carbon dioxide in the bottle, or until the carbondioxide pressure inside the bottles decreased to 318.3 Kpa. Normally, aheavier bottle having a thicker sidewall thickness has a longer theshelf life. The shelf life values are shown in the following Table 14.It can be seen that 2-L bottles made from 50 gram preforms of the PETCopolymer resin have essentially the same shelf life as 2-L bottles madefrom 52 gram preform made using the Conventional PET resin. TABLE 14Sidewall Resin deflection (Kgf) FTIR shelf life Std. Dev. PET Copolymer50 1.63 13.9 week −0.3/+0.4 gram preform Conventional PET 52 1.40 13.7week −0.4/+0.6 gram preform

It should be understood that the foregoing relates to particularembodiment of the present invention, and that numerous changes may bemade therein without departing from the scope of the invention asdefined by the following claims.

1. A container made from an injection molded preform, the preform havingan open ended mouth forming portion, an intermediate body formingportion, and a closed base forming portion and comprising apoly(ethylene terephthalate) copolymer (PET Copolymer) comprising a diolcomponent having repeat units from ethylene glycol and a non-ethyleneglycol diol component and a diacid component having repeat units fromterephthalic acid and a non-terephthalic acid diacid component, whereinthe total amount of non-ethylene glycol diol component andnon-terephthalic acid diacid component present in the PET Copolymer isin an amount from about 0.2 mole percent to less than about 2.2 molepercent and the PET Copolymer is based on 100 mole percent of the diolcomponent and 100 mole percent of the diacid component.
 2. A containeras in claim 1 wherein the total amount of non-ethylene glycol diolcomponent and non-terephthalic acid diacid component is present in thePET Copolymer in an amount from about 1.1 mole percent to about 2.1 molepercent.
 3. A container as in claim 1 wherein the total amount ofnon-ethylene glycol diol component and non-terephthalic acid diacidcomponent is present in the. PET Copolymer in an amount from about 1.2mole percent to about 1.6 mole percent.
 4. A container as in claim 1wherein the repeat units from the non-terephthalic acid diacid componentare present in the PET Copolymer in an amount from about 0.1 to about1.0 mole percent.
 5. A container as in claim 1 wherein the repeat unitsfrom the non-terephthalic acid diacid component are present in the PETCopolymer in an amount from about 0.2 to about 0.75 mole percent.
 6. Acontainer as in claim 1 wherein the repeat units from thenon-terephthalic acid diacid component are present in the PET Copolymerin an amount from about 0.25 to about 0.6 mole percent.
 7. A containeras in claim 1 wherein the repeat units from the non-terephthalic aciddiacid component are present in the PET Copolymer in an amount fromabout 0.25 to less than about 0.5 mole percent.
 8. A container as inclaim 1 wherein the repeat units from the non-ethylene glycol diolcomponent are present in the PET Copolymer in an amount from about 0.1to about 2.0 mole percent.
 9. A container as in claim 1 wherein therepeat units from the non-ethylene glycol diol component are present inthe PET Copolymer in an amount from about 0.5 to about 1.6 mole percent.10. A container as in claim 1 wherein the repeat units from thenon-ethylene glycol diol component are present in the PET Copolymer inan amount from about 0.8 to about 1.3 mole percent.
 11. A container asin claim 1 wherein the repeat units from the non-terephthalic aciddiacid component are present in the PET Copolymer in an amount fromabout 0.1 to about 1.0 mole percent and the repeat units from thenon-ethylene glycol diol component are present in the PET Copolymer inan amount from 0.1 to about 2.0 mole percent.
 12. A container as inclaim 1 wherein the non-terephthalic acid diacid component comprisesrepeat units from diacids selected from the group consisting of adipicacid, succinic acid, isophthalic acid, phthalic acid, 4,4′-biphenyldicarboxylic acid, and naphthalenedicarboxylic acid.
 13. A container asin claim 1 wherein the non-terephthalic acid diacid component comprisesrepeat units from 2,6-naphthalenedicarboxylic acid.
 14. A container asin claim 1 wherein the non-ethylene glycol diol component comprisesrepeat units from a diol selected from the group consisting ofcyclohexanedimethanol, propanediol, butanediol, and diethylene glycol.15. A container as in claim 1 wherein the non-ethylene glycol diolcomponent comprises repeat units from diethylene glycol.
 16. A containeras in claim 1 wherein the repeat units from the non-terephthalic aciddiacid component are 2,6-naphthalenedicarboxylic acid and present in thePET Copolymer in an amount from about 0.1 to about 1.0 mole percent andwherein the repeat units from the non-ethylene glycol diol component arediethylene glycol and present in the PET Copolymer in an amount fromabout 0.1 to about 2.0 mole percent.
 17. A container as in claim 1wherein the preform has a stretch ratio in the range from about 8 toabout
 12. 18. A container as in claim 1 wherein the preform has astretch ratio in the range from about 8 to about
 10. 19. A container asin claim 1 wherein the PET Copolymer is a reaction grade copolymer. 20.A container as in claim 1 wherein the intermediate body forming portionof the preform has a wall thickness from about 1.5 to about 8 mm and aninside diameter from about 10 to about 30 mm, and the preform has afinish, a closed end opposite the finish, and a height from the closedend to the finish of from about 50 to about 150 mm.
 21. A container asin claim 1 wherein the container has a volume within the range fromabout 0.25 to about 3 liters.
 22. A container as in claim 1 wherein thecontainer is a bottle, drum, carafe, or cooler.
 23. A preform having anopen ended mouth forming portion, an intermediate body forming portion,and a closed base forming portion, and comprising a PET Copolymercomprising a diol component having repeat units from ethylene glycol anda non-ethylene glycol diol component and a diacid component havingrepeat units from terephthalic acid and a non-terephthalic acid diacidcomponent, wherein the total amount of non-ethylene glycol diolcomponent and non-terephthalic acid diacid component present in the PETCopolymer is in an amount from about 0.2 mole percent to less than about2.2 mole percent and the PET Copolymer is based on 100 mole percent ofthe diol component and 100 mole percent of the diacid component.
 24. Apreform as in claim 23 wherein the non-terephthalic acid diacidcomponent comprises repeat units from 2,6-naphthalenedicarboxylic acidand the non-ethylene glycol diol component comprises repeat units fromdiethylene glycol.
 25. A preform as in claim 24 wherein the repeat unitsfrom 2,6-naphthalenedicarboxylic acid are present in the PET Copolymerin an amount from about 0.1 to about 1.0 mole percent and wherein therepeat units from the diethylene glycol are present in the PET Copolymerin an amount from about 0.1 to about 2.0 mole percent.
 26. The preformas in claim 24 wherein 2,6-naphthalenedicarboxylic acid is present fromabout 0.2 to about 0.75 mole percent and the diethylene glycol ispresent in an amount of about 0.5 to about 1.6 mole percent.
 27. Apreform as in claim 23 wherein the preform has a stretch ratio in therange from about 8 to about
 12. 28. A preform as in claim 23 wherein thepreform has a stretch ratio in the range from about 8 to about
 10. 29. Apreform as in claim 23 wherein the PET Copolymer is a reaction gradecopolymer.
 30. A preform for use in making a container comprising a PETCopolymer comprising a diol component having repeat units from ethyleneglycol and a non-ethylene glycol diol component and a diacid componenthaving repeat units from terephthalic acid and a non-terephthalic aciddiacid component; wherein the total amount of non-ethylene glycol diolcomponent and non-terephthalic acid diacid component present in the PETCopolymer is in an amount from about 0.2 mole percent to less than about3.0 mole percent based on 100 mole percent of the diol component and 100mole percent of the diacid component, and wherein the non-ethyleneglycol diol component is present in an amount of from about 0.1 to about2.0 mole percent and the non-terephthalic acid diacid component ispresent in an about of about 0.1 to about 1.0 mole percent.
 31. Apreform as in claim 30 wherein the total amount of non-ethylene glycoldiol component and non-terephthalic acid diacid component present in thePET Copolymer is in an amount from about 0.2 mole percent to less thanabout 2.6 mole percent.
 32. A preform as in claim 30 wherein thenon-ethylene glycol diol component is derived from diethylene glycol.33. A preform as in claim 30 wherein the non-terephthalic acid diacidcomponent is derived from 2,6-naphthalenedicarboxylic acid or itsdiester.
 34. A preform as in claim 30 wherein the preform has a stretchratio in the range from about 8 to about
 12. 35. A preform as in claim30 wherein the preform has a stretch ratio in the range from about 8 toabout
 10. 36. A packaged beverage comprising a container made from aninjection molded preform and a beverage disposed in the container,wherein the preform: (a) has an open ended mouth forming portion, anintermediate body forming portion, and a closed base forming portion,and (b) comprises a PET Copolymer comprising a diol component havingrepeat units from ethylene glycol and a non-ethylene glycol diolcomponent and a diacid component having repeat units from terephthalicacid and a non-terephthalic acid diacid component, wherein the totalamount of non-ethylene glycol diol component and non-terephthalic aciddiacid component present in the PET Copolymer is in an amount from about0.2 mole percent to less than about 2.2 mole percent and the PETCopolymer is based on 100 mole percent of the diol component and 100mole percent of the diacid component.
 37. A packaged beverage as inclaim 36 wherein the repeat units from the non-terephthalic acid diacidcomponent are 2,6-naphthalenedicarboxylic acid and present in the PETCopolymer in an amount from about 0.1 to about 1.0 mole percent andwherein the repeat units from the non-ethylene glycol diol component arediethylene glycol and present in the PET Copolymer in an amount fromabout 0.1 to about 2.0 mole percent.
 38. A packaged beverage as in claim36 wherein the preform has a stretch ratio in the range from about 8 toabout
 12. 39. A packaged beverage as in claim 36 wherein the preform hasa stretch ratio in the range from about 8 to about
 10. 40. A method forreducing the cycle time for making a container comprising the steps of:(1) providing a PET Copolymer melt comprising a diol component havingrepeat units from ethylene glycol and a non-ethylene glycol diolcomponent and a diacid component having repeat units from terephthalicacid and a non-terephthalic acid diacid component, wherein the totalamount of non-ethylene glycol diol component and non-terephthalic aciddiacid component is present in the PET Copolymer in an amount from about0.2 mole percent to less than about 2.2 mole percent, (2) then injectingthe PET Copolymer into a mold, (3) then cooling the mold and thecontained polymer, (4) then releasing from the mold a preform, (5) thenreheating the preform, and (6) then blow molding the preform into acontainer; wherein the cycle time for making the container is reduced ascompared to a second cycle time for making a second container comprisinga poly(ethylene terephthalate) resin having comonomer modificationgreater than about 2.2 mole percent of a combination of a non-ethyleneglycol diol component and a non-terephthalic acid diacid component. 41.A method as in claim 40 wherein the repeat units from thenon-terephthalic acid diacid component are 2,6-naphthalenedicarboxylicacid and present in the PET Copolymer in an amount from about 0.1 toabout 1.0 mole percent and wherein the repeat units from thenon-ethylene glycol diol component are diethylene glycol and present inthe PET Copolymer in an amount from about 0.1 to about 2.0 mole percent.42. A method as in claim 40 wherein the preform has a stretch ratio inthe range from about 8 to about
 12. 43. A method as in claim 40 whereinthe preform has a stretch ratio in the range from about 8 to about 10.44. A method for making a container comprising blow molding an injectionmolded preform (a) having an open ended mouth forming portion, anintermediate body forming portion, and a closed base forming portion,and (b) comprising a PET Copolymer comprising a diol component havingrepeat units from ethylene glycol and a non-ethylene glycol diolcomponent and a diacid component having repeat units from terephthalicacid and a non-terephthalic acid diacid component, wherein the totalamount of non-ethylene glycol diol component and non-terephthalic aciddiacid component present in the PET Copolymer is in an amount from about0.2 mole percent to less than about 2.2 mole percent and the PETCopolymer is based on 100 mole percent of the diol component and 100mole percent of the diacid component.
 45. A method as in claim 44wherein the repeat units from the non-terephthalic acid diacid componentare 2,6-naphthalenedicarboxylic acid and present in the PET Copolymer inan amount from about 0.1 to about 1.0 mole percent and wherein therepeat units from the non-ethylene glycol diol component are diethyleneglycol and present in the PET Copolymer in an amount from about 0.1 toabout 2.0 mole percent.
 46. A method as in claim 44 wherein the preformhas a stretch ratio in the range from about 8 to about
 12. 47. A methodas in claim 44 wherein the preform has a stretch ratio in the range fromabout 8 to about
 10. 48. A method for making a preform for use in makingcontainers comprising injection molding a PET Copolymer comprising adiol component having repeat units from ethylene glycol and anon-ethylene glycol diol component and a diacid component having repeatunits from terephthalic acid and a non-terephthalic acid diacidcomponent, wherein the total amount of non-ethylene glycol diolcomponent and non-terephthalic acid diacid component present in the PETCopolymer is in an amount from about 0.2 mole percent to less than about2.2 mole percent, and the PET Copolymer is based on 100 mole percent ofthe diol component and 100 mole percent of the diacid component.
 49. Amethod as in claim 48 wherein the repeat units from the non-terephthalicacid diacid component are 2,6-naphthalenedicarboxylic acid and presentin the PET Copolymer in an amount from about 0.1 to about 1.0 molepercent and wherein the repeat units from the non-ethylene glycol diolcomponent are diethylene glycol and present in the PET Copolymer in anamount from about 0.1 to about 2.0 mole percent.
 50. A method as inclaim 48 wherein the preform has a stretch ratio in the range from about8 to about
 12. 51. A method as in claim 49 wherein the preform has astretch ratio in the range from about 8 to about 10.